Pressures generated in vitro during Stabident intraosseous

Pressures generated in vitro during Stabident
intraosseous iniections
Meechan
J. M. Whitworth, R. A. M. Ramlee & J G'
SctroololD€ntâl Sciêtrcd. NewcastleUni!æitv
Newcastle upot Tvne uK
with
maximum ùÛa-cârtndge pressure development
rniecL:on'
ume w.F prorLcdlor slo$ Ùd raoid
Whitworth JM, RamleeFAM, Me'chtn JG Pressùres and onÈway À\ovA (P < 0 05) conductedto .deteror
inledbns
in waroduringsrâbidên:inÙaosseous
generâred
mine sisûitcani diiterences behdeen categorles
2045'
lnteûananêlEndôdonti.Jouthalsa,291-296
injætion.
atr
Rèsults Presures createdwhen iniecnng tn!Ô
ÛrtraStabident
the
lhat
Aim To test the hvpothesis
r
i
c
sue
I
n
l
o
s e r e l e q sl t d n , b o 5 ' n c Ê d e d r o i n i e c r
techôseous injection is a potetrtiatlv high-pressure
rnÛa{P<0.001). East iojection producedsreate'
rique, which cMies serious nsks of anaesthetic
p.rrtu.ut than slow deliverv (P <! 05)
"*iar"
htsner
IDjeciionpressur€srose more quicklv and to
A s1ândardÀstra detrtal sr{inge was
Methodology
it
leiels in smau vouûg sheepmatdiblesthan Larger'
of locar
moiliiled to meâsure the internal pressure
intra_
old sheepmaùdibles.The absolutemaximuû
anaesthetic cartridges during injection' Intra-cairidge
was
stùdv
cfftridge pressu.edevelopeddurins the
dos
D r e , s u r ,w L - em e a s u r êâdr I s i n t e r v a l sd u : n B
ka'ture
1.31 MPa which is lessthan thât needed!o
ot
i , s p ' , v i . o r " t v l 5 s r a n d r a P i dr < 1 0 s ' i n i e c r t n n s
glass
cartri'1ges
ro/c
zl xvto.oin" w'rh | :80o0o adrerahe
Cônclusions Stabidentirtraosseous'qecrton'onor
resistance)
tisslr€
at
inlo
{no
cartridge volùmeo
instrucin the
itucted iD ac.ordatrcewilh the manufactùrer:
irto freshly prepâred Stabident perforâtion sites
tions does noi present a serious risk of dâùserous
anterior maùdibie ot freshLvcuiled voung aûd old sheep
'as repeated pre$ure build-ùpin local araestheliccadndges'
(against tissue resistaqce) Each iniection
pressÙres
pressure
l0 times oler 3 dats. Absolute maaimum
Keywords: Nraosseous.locâlanaesthelic
p'es
mean
injection
of
câtegorv
Êenelated by each
;ùres at t s interals iD each series of injections ând
)aoq atttpted1i Deûtnh{ 2001
R..eitud6 ocLùbù
mean
slanilsd deviations were calcûtated Ctves oi
cartridscsto tâiL
methodswhich tnâv causeanaeslhetic
ct41 1990)
MeechàD
lntroduction
(Meæhan & Mccabe 1986
lackrng'
h
otten
pro
although detailedeviden e
SùlDlemeDtary injections Ùe olten reeded to
l in
(Mee_
ln(raoseoJs Inle'r:on .s d elTecr:veadiun
pulps
Ioundtv anaesthetizeirreversiblv inllded
rh
and
'!
dl
'LnOJ)
\us'lein
emersencyêndodorriLs
chan 2002). These coûtrol Pain bv ilcreæitg drug
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siand
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with
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soluliorlinto can'ellous
anaeslhetic
ârd dental slnnge and ultra_shorl(6 nml 27-gauge
Dr loht M. WhitwÛrth School o' D'nlal
CoÛ€sbonde!æ:
needle-cortical pertoratorsaûd ûædlesde siæ-marcnea
and toss
sci€.c;. uewdstle Unive6iit, F.adlinelon Plâ'e New'ârdê
iRamlee& \\'hitworth 2001) to avoidbackJlo\t
+44
ùDonlvne NE2 4BW, UK (Tel : +44 791 222 7A2\ iu:
tissÙe
1ow
compliance
ofdrug duringiniectioninto a
ùk)
191 2i2 6117: €-nàil: i m.whit{orth@ncla'
J0umr
@200t rûrenafonâlEndododic
rnc'id]onâlFndodÔilicJoÙmà|'33.291296,2005
E
I
PGs!rc on sràbidên injedion
whitudb
inskuctroN lecolmelrd slow
The mmulactllEk
delivery of on€ quârter cartridge of maestheti'
sôlutioû but make no obs€Fations on the risk ol
pressure build-up dÙing injætiot 'nto a croser
This study wâs designedto a€stthe hvpothBis that
th€ Stabidert iDtraosseoN technique is a potêntiallv
high-pr6s,Ie technique, which cùies serious risks ôt
anaesthetic cdtridge tailure.
Materials
1
d'r'
and methods
Development of a syst€m to m€asure fhe internal
pressure ofdental local am€sthctic cartridges during
injection
Où e{perjmental system was based on the modiÊed
Astra sylinge model of Maita & Hooichi (1984)
(Iis. r).
B.ieliy, a standard Astra (Asûazeneca Maccles_
ffeld, iJK) dental syringe w6 modifled bv the additioD
of a 2o'gaùge slâintes steel needle inserted ând
secùed through the hoEing of the bdrel (Depart
ment of lngineeriog, University ol N€w@stle,UK)
This was connæted to a pressure transduær IRDP
Ëlectronics. WoLverhampton. UKi pressure range
0 1000 psi (0-6.89 MPâ)l which was nounted
on the syringe bùrel. This in turn wâs conrected
to a mic.ôprocssoÈbasedstrain ânplitier (E525
Cyphec Â)P Electronics).fftted with a stlndârd
R S 2 J 2: n r r l d c p t o . o m m u n n r t . o nw i r l l h e h l ! " terniûal progranme for Windows 95 (Hilgraele Inc..
Monroe. MI, USA), allowing the capture ot presure
readiûgs from the strain âmplifier and pressure
transdùcer. The presure transducêr and slrain
amplifier were calibrated by the sùpplier p.ior to
Pressurc m€asurement
stmdard l@al amestheticcâ.tridges122ûl' oî 2%
xylocaine with 1 : 80 ooo âdrenaline (Astrazeneca)l
r{ere marked to indicate 0.25 cùtridge volumes belo.e
loading irto the modi{ied Àstra sFioge {Astrazereca)
carrying a StabideDtultra short (6 nm) 27-gauBe
neede A sene<otpr6'ure rtrordinBcwas màdedLrrins
thê injectionot 0-25 cartridgevolumesiDto:
l. Âir (no tissueresktance).
2. Fresh Stabidentperforalionsites in the dentate
anterior mandible ot:
{a) two lreshlycûlledyoung(approxiûatelvI vea.old)
4 vearsold)
tb) tso lreshlyculledold {approximately
New pùnctur€ holes.needlesaûd ca.tridg6 were
employedfor eachinjection.
The presureswhich delelopedin the svringeca!tridse were recordedat 1 s itrtertâls drring a seri.s .l
10 slow lapproximâtelyr; d ând 10 .apid (as rapidl!
s possible:<10 s) itjectioDsinlo air and irio shæp
lnjectionsit eachseriesdere spreâdover I dâvs1o
avoid operâtorfatigueand to allow disperealot local
ârâesthetic$'ithit the specimeù-AU injectionswe.c
made b! a slngle.Iemaleinlestigator (RAMRI Locâl
anâ.stheticcâ.l.idges employedin this study $€re
stôredaùd adûitistered at rôom temp€râture Sheep
'C) and
rândibles {.re storedùùde. retrige.alioDl'l
allos'edto eqùilibrateto foorn tempe.aturefor 2 I h
hçloreinjection.
'lhe
absolurenaximum presures senerateilbv each
series of iùjecdons.meàt pressu.esand standa.d
by:
oenlalcarldgesynnge,modiilêd
. p@s*rc lÉnsduær mounlêdI
. addiuonai
20oausenædlê!re€nêdIhrcugh
Fisur. 1 Sch€naôcdiagGn ollocal
aùacstheti. presu.€ tdtina syslen.
litmâtonâl Endodonli. J oon 3L 3a, 291-296, 2005
ÊndodoûitJou'ial
@2005Inrârôarionâl
$fti@nh d dr PG.su€ on srabidsnrinjedion
deviations were catculated with Microsott E\cel f'r
Windows XP. Cunes of mean maximum nEa{d
hidge pressue developmentwith flme were plott€d lor
slow ùil rapid idections in Microsoft ExæI, and oftway ^NovA (coDfdence intewal P < 0 05) condD't€d
to.letemine significmt di,Ierencesbetwæn the vmoùs
câa€goriesof iDiectios.
Mdimum pressùe recorditgs were @mpaEd with
publshe{t Weibûl curves of local anâesthetic cartridge
failure iMeechan st al. 1990) to Provideiûsight info the
tikelihood of systen lailure rÊsulting ftom the intracârtriilse pressuressenerated dÙing use of the Siab_
ident intrâosseousmethod
Results
The ntatr ndimum md absolute maximum intracartridge Pressuresgen€rateddÙing iniecaioDsifto aa'
and sheepnâtdibles are show! in Table 1
Mdimùm anil meaû mdimum intra-carbldge prs_
sures were alwâys greater duriDg irjectioE iDto tisue
compard with air. where there was no exi"nai
(P < 0.001)
resistance
duing inic.uo''MPalIr -- l0l
Tâblè1 P'6sùesgenPraL"d
Meânm6timum
prêssu@(MPal
in 3eri6 {sDl
Absôluremôimum
(MPâ)
pressÙrc
in sêries
Râpid iljection alwavs generated highd absolut€
md mean mâximum intrâ{artridge prsMes thân
their respe.tive slo& injection (P < 0 05) The'e were,
howwer, no statisticallv sigtiflcæt dilTerencesbetween
the meân maximum and absotute maximum inrracarûidee pressùes geDerateddurins slow iûjection Dto
yoùs or old sheepmandibles, or .apid iniection idto
youns or old she€Pmandibles
Curvesilloitra!'ls the developmentof intra'câ'bidge
prcssureÙirh ÙmPtor slow iniecrionszre shown i"
Fig. 2. Slow itrj€.tion into air (ûo tissue resistanæl
creatld a small nse ilr intra'cartddge pressure' whi'h
peaked after approximatelv 4 s and remaiDed steadv
throughout the iojectiot period- Âll iniections 'ntÔ
tissue $€.e arsociatedwith similâr profrlesof pressùre
inc.@se, Peakins between 7 and 10 s at lêvels
betwætr 1.4 and 1.68 MPa. beforedecliningtowards
the end of the injection
Grcate. vaiation wæ sæn âûongst the rapid
injectiom (Fig.l). Iûjecting as quickLvas pos$D€
without tissùe rsistance resulted in a pattern ol
pressùe beha\iolr which wd similar to the dow
irjection. Intra-cartridge pre$u.e rose to a peak àt
approximâiely 5 s. and remained relativelv co!'shnr
until the end ol the injection pedod
Sharp increasesin presure wêre noted dûring the
tust 4.{ s ot injeciioD against issue resistance wiih
both the rate of developnentând peak valùe being
greatestill the relatieelvsnaLLvoùng sheepmandibleDiscussion
Pressuregenerationis .ele!an! to the €lIectivenessând
safery of sme local anaesihetic melhods (Lht 't dl'
1988. Vancheluwe & Walion 1997) The intrari-
1.6
o.2
Fisurê 2 Me& danmm in[a@aidse presù€ {MPa) vesùs t'me (s).
€ 2005lniemarion:l
onti. Jô!md
€ndôd
@
Presurc on sbbidsnt injsdion vr'hr'en' er ar
Flgure3 I'teat maximÙmint.a{âr_
tridseprcssué{MP€)ve6us time G)-
gamentary iniection mây, ior exmple, gene.ate hish
p.essures,
aspæiallyin combinaiionwith commer'ial
pressuresyring6 (walnslev .tal 1989) Few data
hdvê bepn âvailable on presrùrs senerareddurins
iDtra{seous injection where sÔLutionis depositedintd
a low compliâncetissæ spâce.
have desclibedsvstedsl'r
A tumber of researchers
pressure
local
anaestheticsvstems(Pâshin
measùring
1984, Rieu .t dl.
&
Horuichj
Maitâ
Leyst al. 19s1,
interestwas
Our
spæific
et
41
1989)
1989, Walnrsley
neasured
readilv
pre$ure
which
wâs
intrarartridse
(1984)
as
de$ribed
method
by the Maita & ltôruichi
Simulationmôdelsare wideLvenplovedin biomcdi
'Ihe iimited availabilitvof whole denrâte
cal reseârch.
lhe use ol an
humân cadavermandiblesnecessitated
model io the
mâlnûâlian
alternative.rnedium-siæd
were
mandibles
ovine
Fresh.
dentate
cunent research.
was
mandible
anierior
only
the
leadily sourced.and
was
efangemeD!
shape
and
utilired. where tooth
to
specrrlâte
are
unable
We
comparableto the humù
on the compârabilityof our own results with thôse
llketyfrom injætion into the jaws oi iiving creatures.
De.prre.on.iderdbleelTo'tro ôrandâ'diæ'nic' ri^n'
soûe degree of operator vanâbilitv w6 ioevitable.
lh.s was panjculaly ço lor rapio iniections necesi
tatiûg trequent breaks and spreâding iniections over
I days. It was r&e for even the slow iûiections tÔ be
smoothlvand consistentlvdue tô the
siven absoluteLy
behaviour oi the cdtridse rubber pilnger' s'hi.h
iypicalljr moved along the cartridse berel with a
judderûg motion. Even a mechanicalsvringe driver
could not deliver truly smooth iniections. ttowever.
the iniectionswere clinicallv realbtic and the stânded denarion( 'ndi@te ân a..eptable l.\el ot consiJ_
@
Multiple cortical perlbrâtions and iojeclions did not
resùlt in aoy clear pattern of presure reductionor
incrêaseaslhe serieslrog.essed.Flùidwas not ûoted1()
emergethrough perlorationsites
providessomeol the first evidencc
This inv€stigation
generâted
in locai anaesthcticcartridges
on prelsùres
iniecnôn
during the lrseofcontemporârvintraosseous
s'ere
rccordings
Presure
techniqùesin the ùandible.
(
1
9
8
1
)
s'h'
e
l
n
i
o
t
P
a
s
h
l
e
v
c o m p ù r a b l e , 1 i lt bh o s e
prcssurs
into
the
iasa ol
repo.tcdmaximuù injeclion
MPa
It was
àtd
1
24
1
91
dogsin rhe raùgebet$cen
iu
less
rvere
highcsi
pressùres
noted thât iniectiot
i'rlecnon
int.à{sseous
dhtensibledssues.$ith the
highe.maxirDumpressure(2.1j8I'lPa)Lhaù
developiug
papilla
r2.11 lttPa). periodotlal lisam'ùr
incisive
. â r d p a l a t e{ 1 5 1 M P a ) â n d i n t r a p u l p à l
{ 2 . 1 5N l P a ) h
l1-19l\'lPâr i]liections.Other fesear.heb hâre nolcd
even higher iùtra-cariridgc PressLre genc.ârinn
(4 MPa)during rr !ùro simulalionoi inraliganreÔtârl
ând inrao$eous irjecLiôns.Bv con!|ast. Shephdd
the iùtrabÔnvprcssureDcr'âçe
.t dj. (2001rùr€àsured
during iùection of $vi,re oràtdibles. and reporred
pressureiDcrcases
an orderoll0lo$€r thaù the los'est
intra'.ârtridle presure dùrins slow iniectioùagâ'nsf
.ecordedit the prcsentstudy
no resistance
Some ot this itconsistencymust reflect detôls ol
protocol.inclùdilg the iniectionrecipietrt.the vohrmc
ot anaesthericdeln'ered.lhe rale of deposition thc
measudùgsFreû. the tempefatureot the cartridge
(Me€chan.l al. 199t) .;rl the site measured Lù
additiot. the len$h and sâùgeotthe leedle influences
pressuregeneratedin denlal local ânaeslheliccÙûidges(i\ieechât& Mccabe1986)- It cân be inlerred
iniectionsvstemsdo not develop
thât loca1anâesthetic
consisteDtin.reasesin pressùreth.oùghout ID the
whiôrcnn e. aL Fcsure on Srâbident inj€dion
prserlt work, the small mandiblesotvoung sheepwere
associaleilwith morè rapid and hisher peak pressureol
inj€ction than la4er, mature sh€ep There is a næd to
standùdize methods lor evaluating this importÙt
elemeDtol local anaestheticdeliverv ând safetv.
So$,ray (1983) stated thât anaesthetic cartridges
were desi$ed to resist approximatelv4-1 MPa oi
pressur€.Previous investigations (Meæhan & M'câbe
causing
1986) haveshom that ihe rangcol pressDres
fracture of 2.2 mL Xylocaine (Astrazeneca) dettâl
ânaeslhetic cartridges ot the tvpe emploved h this
s r u d yw e r eb e j o n dr h i r ! à 4 B Pr ( \ l l q 7 V P a
The mdimum p!6su.es etrcoùntered, even whet
injections were aiininistered as rapidlv as phlsicallv
possible.
wereno higherthaû 3-I 1 MPâ-lt is impor.ant
to poitrtout that the operatoriû lhis studv was iemâleA previousinvestigationhas shown that mâle operato6 can geDerate8r@te! prssÛes thatr females(Maita
& Horuichi 1984). In thât studv (ùlaita & HÔnri'hi
28% sreâ!r9S4), maLescouldproduceapproxinateLv
e. maximum lorce. If the forcesrecordcd in the prcsent
study were inùeasedby 28%, this is still below that
ûeededto lracture glæs cârtndges.lt cÙ be concluded'
therefo.e, that glass Xvlocâine (Âstrazeneca) ânaesthetic carkidges we.e at no significant risk ot iracture
during iûkaoseous injætion bv the Stabidenldetbod
The forc€s reported in this investigation are less thÙ
lhât reported duritg intrâligametta4' iDjcctions
i\4'almsleyel al. l989l Inlrâlisameitarv injections
ire considered â type ol intraosseous ânâesthesia
rsmitb & Walton 1983). AltlDugh iùtràligamertaq'
ûijec'
anàesthesia
may be cotsideredan intraosseoùs
tbt from a physiological poilt of view. the trûe
intrao$eoustechniquedilïe6 in a nechanical sense
in that lessforceis generatedin the ca.tridgeltith lhe
l'laslic Locâlanaestheti.cartridgesare known to tail
b.lween3.Ol and 6.89 MPa.The peakintra{artridge
njccuon
F.esuredevelopeddurins slow intraosseous
was<1-67 MPa,thus plasticcartridsesare at litde risk
ol tailureduring Stabidentinjectionswhen the iniection
is given slowly. Examitation ol Weibull dhtribution
.un'es (Meæhanst 41.19901suggeststhât if hhaossrus injectionwas given very râpidly (peakpressure
l.]l MPa). there may be a lO-15% risk oi plasti.
ca(ridgetàilure.Plasticcartrideesfail dùe to dislo.tion
ot lhe câdridse plunger wilh loss of an'esthetic
dution. .ather than daûgeroustàilureotlhe cartridse
Nalls1Meæhaner di. 1990). It can be susgestedthat
tlanic and gls anaestheticcart.idgesmay be used
rvirh safetyiD the Stabidentinbaosseoustæhnique,
C2005]n&hdioiâ]EndodonlicJouftâ|
plovided thât the mmufacturer's instructions ior slow
injeclion ùe followâj.
Within the timitations ot this slùdv, the working
hypothesisthat the Stabidentintraosseoustechnique r â
potentially high prssure technique which ce.ies serroN risk oiânaesthehc cdtridge failure was disproved
Conclusions
Stabidett intraoss€os injection conducted in accord
anæ with the manu-facturer's instructions does not
p - e s e nâl s û i o u s' l 5 ko l d â n s e r u Ùprr P $ u r b L r l du p n
local anâ$thetic cartridges lt is importarlt to note that
the.recomended needle letgrh atrd gâuge was used
As the lorces prodùced withitr the cartridge û'iLt
increâse with longer atrd naûower needles(Meechât
& M.Cabe 1986) the presentresultr should not be
ertrapolatedto coverall intrao$eousinjectioos
Refelences
l (2(r0l)
A. NùsteinJ Becku Mrearêr
GâllatinJ, Reader
c o r p a r r o . o l L w oi n l t c o s € - â n - r l a , r < h Ù r or " "
oandibular posteriortcetb. l"M1al ol 1lû AnktirdùDrrtal
l3!1. 1476 34,
.4rso.idlion
L ' . ir i .M " r n j ê rl -I r N e nE A P r P v l H
to vùios slutionslsing rhc inlraliganrenfluidresponse
Lâryinjecliôtr.0!i, .ss?n.4Llle,Idliondj19 ii9-61'
Mâita É. H.ruichi H (1984) Àlea.u.êmentor prcssures
developêdin the slriûge du.ins denralinlilt.âlon araes_
rhesiâ.BriIisftD.nlnlJdxnlal156 199 111{)
routest! loral aÙ'èsih'
iucecha. iC 12O0ll Sùpplemeniary
15 83i-96
rindodoùti./rrddl
siâ. trterndrional
McechanJC,MccâbeJF(1986lA modelior inlestigalingthe
p.obabilityoi t actùreÔfdentalldal ânacnheli'cartridges
sririsl D4xal /o!nr.l 160. 316 8
L{Jcal
ÀfecchanlC.MccabêlF CarrickîEt1990)Plasticdêntar
anaesrhêticcr.tridgesra labo.aroryin!.nigârion B'ilislr
DolLùllaumdl 169. t4-6
À{edhân JC. DonaldsonD (o111.*i^ l199tr Thc efle'h ol
storage tetp€rature on the resistancelo aa,u.e of dental
locâl anaesthetic carEidsd. Idrrndl oI l/t CnndddnDdnkl
,4$ô.i4tidn6r. 141-8.
Nùssteini. ReaderA. Nist R. Be.k rl. uevers wl (1993)
inl.âo$cousrDrN_
Andthetic efii.acyol the supplemcnral
tion oI 2% lidocâine with l:100000 epincphrinc In
ineveFiblc pulpilis- /ourndl oJItriorionrir's z r' 437-e l
Nustein l. Jcnnedys- Reâder BeckA Bcckùt. Wcâvê' l
(2OOl) Anaesthericeûicacv oi thè supplementalxtip
iltraossæusiniectionio p.tienrs\'i1h irrele6ible ptrlpilis
Ianlal ôJ Endodoùûs29 724 a
PâshlcyDL,NelsotR, PashlevDH I 198l I Presurd creatcdbv
dentâlinj{liots. /oxnl(l o/D.rlal R.i.dr.[ 60 1741 8'
Pæ!rc
on Sr.bid€d Inidio.
l\ôivo..,
étâr
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